I'm about to experiment with rock salt and the effectiveness of it as weed killer. There are a few areas on the lot that we never want weeds EVER, and as it's less dangerous than Round-up and other chemicals, and supposedly has a lifespan of 5 - 10 years, it will be cost effective too.
I'm trying it on a small area before we implement it for regular use. I've read that it'll take about 3 applications, barely using a box of rock salt at a solution of 1 cup of salt per 1 gallon of water. After that I hope to only use tiny maintenance amounts for 10 years until I need to use another box or two. My lot is small, only about 260-ish units and parking spots, with some commercial tenants in an upper parking lot as well.
Have any of you used this method before? If so, How many boxes of rock salt would you say could cover 1/2 an acre? Most of the major areas have new pavement, and we don't get a lot of weeds. I got this idea because I'm a history nerd; lots of random historical facts that i find interesting, but actually pays off occasionally.
I will update this thread with my progress.